This invention generally relates to optical equipment and more particularly to a projector for producing a night sky illusion on a planar surface such as the interior ceiling of a room.
From the beginning, humans have regarded the heavens with feelings of wonder, fascination, awe and sometimes fear. Major heavenly bodies were regarded as gods by early peoples and clusters of stars were imagined to resemble mythical creatures and persons that paraded across the nighttime sky. Out of people's need to understand and rationalize what could be seen in the heavens was born what is possibly the oldest of sciences, astronomy, and a countless number of fables. Viewing of the nighttime sky remains a pastime enjoyed by young and old alike. Unfortunately due to adverse weather conditions and the realities of urban living, such an experience is becoming increasingly rare for most people.
A popular substitute for actual viewing of the stars is a planetarium. By permitting indoor viewing of simulated portions of the night sky, a planetarium provides a year round source of astronomical education and entertainment. Typically a planetarium will have a spherically shaped ceiling and a projector mounted at the approximate center of the sphere. The projector will include a small rotatably mounted sphere and an intense light source mounted within the sphere at its center. The surface of this sphere is opaque and includes a large number of tiny holes. The holes are positioned so that when the projector is illuminated the light transmitted through the holes in the sphere will form light patterns on the ceiling resembling star, planets and constellations as they would be viewed from the earth's surface. By rotating this sphere, the apparent movement of these bodies due to rotation of the earth can be simulated. Also by properly orienting this sphere, portions of the heavens seen at different times during the night and different seasons of the year can be viewed. A visit to a planetarium is a unique experience, and many people have expressed a desire to have a planetarium in their own homes. Unfortunately, because of the expense and structural complexity involved in building a planetarium even on a small scale, this would not be possible for most people.
Accordingly, it is an object of this invention to provide a projector for creating a night sky effect on a ceiling which is relatively simple, inexpensive and practical for residential use.
It is another object of this invention to provide for such a projector in which the night sky image is created using a substantially planar transparency, thus eliminating the more complex spherical lens assembles used in planetariums.
It is a further object of this invention to provide for a process for creating a night sky image on a ceiling using luminescent paint, thus eliminating the need for continuing use of the projector.